page zoom vs text zoom

It was clear from the start Torsten had made up his mind. He has demanded everyone else provide evidence, then tells them it's not good enough when they provide it. He has ignored user needs which don't fit with the ideas he is promoting. And all while providing no evidence to back up his own position.

It's one of the worst sorts of argumentation, imho, since it wastes so much of other people's time. To be honest, I hadn't expected this from Torsten.

Hopefully the rest of us can use this thread for a constructive conversation about the pros and cons of page zoom and text resizing. And who knows, maybe he'll admit he created this topic as a soapbox and go back to his usual, reasonable self.

Yes they were. And you may be righ that this still happens in ff when resizing text, although it won't shrink the images as Opera does.

Your original question was were there any reasons for zooming as in Opera, being problematic. My answer still stands, that resizing images as well does cause problems, as shown above. With the added complication of the resizing being less predictable due to the propriatry algorithm making 'smart' resizing decisions, which are not always that smart. As with the CNN page.

It was clear from the start Torsten had made up his mind. He has demanded everyone else provide evidence, then tells them it's not good enough when they provide it. He has ignored user needs which don't fit with the ideas he is promoting. And all while providing no evidence to back up his own position.

It's one of the worst sorts of argumentation, imho, since it wastes so much of other people's time. To be honest, I hadn't expected this from Torsten.

Hopefully the rest of us can use this thread for a constructive conversation about the pros and cons of page zoom and text resizing. And who knows, maybe he'll admit he created this topic as a soapbox and go back to his usual, reasonable self.

Yes that's right Ben. I also steal candy from babies and scare little children - oh, and I park in disabled bays

Phil Teare wrote:

Do you see my point?

Absolutely.

I really am genuinely bemused as to how this discussion became so contentious. I don't think I've been unreasonable, but if the vote is unanimous then I guess I must have been.

The ones starting from 'test' are raw screen shots, ts = text sizing, pc = percent zoom. I mostly use Yahoo as an example. I was mostly interested in the quality of image re-sizing, which was better than I expected.

Before saying what works or doesn't, I'd like to set up the scenarios of use. Zoom is helpful to people in these situations (not all of which I would classify as accessibility in the strict sense):

1. Someone with normal vision, who simply wants bigger text to make the site easier to read.
2. Someone with normal vision who needs to increase the size to read it (whether because they have forgotten their glasses, or have a high-res laptop monitor that goes fuzzy at smaller resolutions).
3. Someone with dyslexia or other cognitive issue that prefers larger text for reading.
4. Someone with reduced vision, but doesn't need a screen magnifier. (I.e. to use a computer normally). This person might (if they know how) adjust the system settings to make everything bigger, but may not.
5. Someone with reduced vision who needs a screen magnifier at 3-8 times enlargement.
6. Someone with significant vision impairment (VI) who switches between screen magnifier and screen reader depending on what they are doing.

If there are any other user groups that might be affected, please do chip in. I've done usability testing with each of these audiences, although they didn't always make a display preference known without asking.

I think the first thing to settle is what level of zoom is actually appropriate in a browser. It's all very well saying that sites don't cope with 400%+ zoom, but does anyone actually use that?

When working with people with VI, you find that (and this is quite logical) they tend to use browser/system settings up to a point, but once you pass a point, use screen magnification and fairly normal system/browser settings.

The point being that I don't think browser zoom is particularly relevant above 300%, because if you need that you'd have trouble using a computer at all. So we are really talking about groups 1-4.

For groups 1-3, the difference between text and page zoom are rarely significant, unless the site uses imagess for (small) text.

For group 4, I think page zoom offers some very useful benefits, as it is good to get the image increased.

In general, I can't see groups 1-3 being harmed by only having (or using) an Opera style zoom.

Now, the implementation: I'm have mixed feelings about IE7's zoom. On one hand, it's good that they have started down this route, on the other hand, the implementation may put people off.

It could put users off because of the horizontal scrolling issue, and it could put developers off doing liquid layouts. It is infact punishing people who have designed with accessibility in mind.
They have all but said that the horizontal scrolling is a bug, it's the main feedback they received and is high on their list of changes. If you read either of my related articles you'll see that I haven't been able to get IE to use a 'max-width', I suspect it's very difficult with their rendering engine.

Also, IE7 still doesn't allow resizing of pixel sized text.

Phil pointed out the IE (5.5+?) feature for zooming which behaves much more like Opera's, trying to fit things in the viewport. Without a lot of testing I'm prepared to assume they are roughly equivalent, except that it doesn't re-render images, it pixelates them.
If you check IE7 & Opera at 400%, you'll find the images are scaled smoothly.

I can see where Torsten was going initially, if everyone had an Opera style zoom, developers wouldn't have to worry about text in images or relative sizing. Perhaps this is why WCAG 2 dropped relative sizing?

Unfortunately, until IE 8 (if it gets it right) or Opera gets into the corporate workplace en mass, I'm not prepared to do that.

I hope you guys don't mind me opening up an old thread, hopefully I can contribute and move it along somewhat. Unfortunately I missed this until Phil pointed it out recently.

Not at all. Nice work

Alastc wrote:

Unfortunately, until IE 8 (if it gets it right) or Opera gets into the corporate workplace en mass, I'm not prepared to do that.

I completely agree, though it doesn't stop me dreaming

It's reassuring to know that my assumptions are backed up by some real world research/experience. I won't say any more as I'm likely to be repeating myself. My views are well established at this point in any case.

If IE8 [7.5?] Goes the route Opera did, in makeing a 'smart' alrgorithm to choose what gets bigger and what gets shrunk, then I'd say its not a solution to liquid design via Tech/device dev. Its close, and worth a pop, but not a full solution. (see images earlier, re opera breaking most news sites I vistited).

Yes, I think the Zoom style property is IE5.5+ Which means its the most ubiquitous by far. And it breaks very few pages. But does still break some (far fewer than opera)

Anyway, I'm repeating myself.

Are there any VI Opera users listening in? Do you/can you relly on Opera's zoom?

The one thing I'd say is dead wrong about your post, AC, is:

Quote:

3. Someone with dyslexia or other cognitive issue that prefers larger text for reading.

Many such users need AT. By the above you imply that all just prefer AT. Small point, but very important to those who need it to be understood.

I don't think we are going to get much further with that line unless someone can say how the zooming algorithms work for Opera & IE's CSS zoom (IE7's zoom is fairly obvious though!). There are simply too many connotations of how pages & layouts can be set up.

Phil Teare wrote:

The one thing I'd say is dead wrong about your post, AC, is:

Quote:

3. Someone with dyslexia or other cognitive issue that prefers larger text for reading.

Many such users need AT. By the above you imply that all just prefer AT.

I wasn't trying to imply anything about the need for AT (assuming AT = Access Technology), just the need or preference for browser zoom.

I understand there is often a need for AT (even if the individual doesn't realise). A couple of my friends are dyslexic, but refuse to use anything 'special'.

I get some strange results, on BBC news it doesn't expand the text links at the top, and on my site it just moves the site to the left without expanding...? I must be doing something wrong?!

With the optional 'shink to fit' button, I still think Opera's method is more polished and friendlier to well made sites. For example, if you open 456BereaStreet in Opera (without shrink to fit), it expands quite a lot before it adds scroll bars, then when things start spilling over. At some point something has to give, so it seems like a reasonable way of doing it.

IE7 zoom goes straight to scrolling, and the IE CSS zoom shrank things, although that could be a ropey bookmarklet so I'm interested in how the talklets one works? (A quick screenshot perhaps?)

(edited addition:) With regards to Opera shrinking things, was that CNN.com? That is only when you've got shrink to fit window, and only when they wouldn't fit in the viewport anyway. The top nav is a table of images, with no way of wrapping, so it would either scroll or shrink, and only if it wouldn't have fit anyway. The IE CSS zoom created scrolling, so I'm not sure where you were going with that one.(end edit)

But I'm straying from the point, I have two questions:

Assuming any page-zoom worked well (didn't shrink anything, and intelligently fit things within the viewport), would it be ok not to have text zoom?

Secondly, could you describe the difference in experience that increases to the text size have for someone with dyslexia? I.e. what the problem is without having larger text, from an experience point of view?

I've tested with a few people with dyslexia, and it hadn't come up. Things like colours schemes, writing style, spacing and links did, but not size of text.

Yes in short there's little between the Opera and the IE css zoom. Opera has its advantages, and will work better on some pages (like 456BereaStreet and to a degree the BBC). So I won't argue the toss on that.

Quote:

Assuming any page-zoom worked well (didn't shrink anything, and intelligently fit things within the viewport), would it be ok not to have text zoom?

From my perspective, yes. It would be ok, but why get rid of it if others like it. Practically, other zooms do break many pages (inc IE CSS), so text zoom is good as a backup.

Quote:

Secondly, could you describe the difference in experience that increases to the text size have for someone with dyslexia? I.e. what the problem is without having larger text, from an experience point of view?

I used to wonder (as did people who knew me) why I'd (and still do) put a news paper right up close to my face, when I have very good eyesight. And had excellent eyesight when younger. Apparently it is likely that I, like many if not most dyslexics, have Irlens (scoptic sensitivity). Essentially what happens is, that nerves used to pass retina information to the brain for processing, effective fail to refresh efficiently, and create an exagerated motion blur effect to perceived vision. i.e. As I scan my point of focus across the text, parts of the chain are holding things up, and consiquently I can't see the next word for fraction of a second, until the slow coach nerves in question sort their backsides out. Upshot is, small high contrast text can be seen, but not read (fluently). Part solutions include, lower contrast text, and bigger text.

So Scoptic Sensitivity is a bit of a missnoma. I'm not overly sensative to contrast. Its just that my eyes are slow.

Imaging instaed of eyes, you saw everything through a high rez webcam. If you stare at something, you can see it very well. But as soon as things start to move, you loose all detail. Big shapes are still disernable, but smaller bits and bobs are just not there yet. Until you stop scanning and stare straight at them.

Prof John Stein at Oxford Uni has done some excellent work in the area, as have many others...

Re: Text zoom
[quote="Phil Teare"]From my perspective, yes. It would be ok, but why get rid of it if others like it. Practically, other zooms do break many pages (inc IE CSS), so text zoom is good as a backup.

I wouldn't get rid of it, certainly not yet, however, I do think it may not be needed in future. Although there isn't much between the IE/Opera zoom, there is quite a bit between 'zoom' and text-enlargement.

If the site fixes the height on elements, you loose readability very quickly (And this is to spec, Firefox isn't wrong to do this). Since Firefox is likely to add a zoom (they're working on the graphics aspect already), Safari is likely to add a zoom (OSX will have a 'resolution independent interface'), and IE will improve it's zoom, perhaps relative sizing will not be an issue anymore?

Quote:

i.e. As I scan my point of focus across the text, parts of the chain are holding things up, and consiquently I can't see the next word for fraction of a second[...] Upshot is, small high contrast text can be seen, but not read (fluently). Part solutions include, lower contrast text, and bigger text.

Imagine instaed of eyes, you saw everything through a high rez webcam. If you stare at something, you can see it very well. But as soon as things start to move, you loose all detail. [...]

Make sense?

Yes, thanks. I guess that larger text helps 'navigate' the text as you read?

After I had laser-eye surgery on my weaker left eye (only), it went from being twice as bad, to twice as good as my other eye. So walking down the street it mostly takes over as the dominant eye, picking up more detail that the other.

However, my right eye still seems to be better hooked into brain function, because it will recognise a face before the left. The left will see all the 'bits' earlier (nose, mouth, hair etc), but the right will put them together as Xs face much quicker. It also takes over when things start to move quickly (like when I'm windsurfing), the left still isn't as active.

Not the same, but just trying to give another example of the difference between sight and understanding...

Text sizing is pretty easy to develop against. The mechanism involved is very straightforward: multiply all em measurements by the current text size setting. The simple way this works doesn't change and is mostly consistent between browsers. What happens in one desktop browser mostly matches what will happen in any other desktop browser, apart from CSS support bugs.

In contrast, proprietary zoom functions are impossible to develop against. The mechanisms involved are very complicated and, afaik, not published. They differ greatly between browsers and can change between browser versions. In Opera, the zooming even has several different modes. What happens when you zoom in IE7 can be radically different to what happens in Opera.

Page zoom cannot replace text sizing because they fulfil different roles. Each can work better than the other in some cases. Neither is perfect but they are both useful, imho.